package com.itheima.reggie.controller;


import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.UUID;

/**
 * 文件上传和下载
 */
@Slf4j
@RestController
@RequestMapping("/common")
public class CommonController {

    @Value("${reggie.path}")
    private String basePath;

    @PostMapping("/upload")
    public R<String> upload(MultipartFile file){
     log.info(file.toString());

     //获得原始的文件名字
        String originalFilename = file.getOriginalFilename();
        //截取文件名称后缀格式
        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));
        //使用uuid重新生成文件名，防止造成文件重名造成覆盖
        String fileName = UUID.randomUUID().toString()+suffix;

        //创建不存在目录
        File dir = new File(basePath);
        //判断目录是不是存在
        if(!dir.exists()){
            dir.mkdirs();
        }

        //将缓存过来的临时文件保存下来
        try {
            file.transferTo(new File(basePath+ fileName));
        } catch (IOException e) {
            e.printStackTrace();
        }


        return R.success(fileName);//上传成功返回文件名

    }

    /**
     * 文件下载
     * @param name
     * @param response
     */
    @GetMapping("/download")
    public  void download(String name, HttpServletResponse response){

        try {
            //文件输入流，读取文件内容
            FileInputStream fileInputStream = new FileInputStream(new File(basePath +name));
            //文件输出流，响应给浏览器展示图片
            ServletOutputStream outputStream = response.getOutputStream();

             int len=0;
            byte[] bytes = new byte[1024];
            while ((len=fileInputStream.read(bytes))!=-1){
                outputStream.write(bytes,0,len);  //从零写到len
                outputStream.flush();
            }
            fileInputStream.close();
            outputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }




    }
}
